Fig. 8.

SKI-178–induced CDK1 activation results in MCL-1 degradation. (A) Whole cell lysates from the indicated AML cell lines were subjected to Western blot analysis to assess expression of various antiapoptotic family members (Bcl-2, Bcl-xl, and Mcl-1). (B) HL-60 and HL-60/VCR cells treated for 24 hours with SKI-178, RO3306, or a combination of SKI-178 and RO3306. Western blot analysis was performed on whole cell lysates using indicated antibodies. (C) HL-60/VCR cells were synchronized at the G1/S phase transition using a double thymidine block and released into either vehicle or SKI-178. Cells released into SKI-178 were either maintained in SKI-178 alone or cotreated with RO3306 14 hours after release. Whole cell lysates were collected at indicated time points, and Western blot analysis was performed using indicated antibodies. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) serves as a loading control.